Case Files Pediatrics, (LANGE Case Files) 4th Ed.

CASE 59

A 2-year-old child suddenly develops inspiratory stridor, tachypnea, and chest retractions. He had been playing alone with his 6-year-old brother before this episode. He is afebrile. Apart from the stridor, his lung sounds are clear, and his physical examination is otherwise normal. A chest radiograph reveals no abnormalities.

Image What is the most likely diagnosis?

Image What is the next step in management of this patient?

ANSWERS TO CASE 59: Foreign Body Aspiration

Summary: A 2-year-old child who was previously healthy experiences sudden onset of respiratory distress.

• Most likely diagnosis: Foreign body aspiration.

• Next step in management: The child’s airway should be evaluated with bronchoscopy. Intravenous access should be established for administration of maintenance fluids and sedation for the procedure; the child should take nothing by mouth until his respiratory distress resolves. Oxygen saturation should be monitored closely.

ANALYSIS

Objectives

1. Recognize the signs and symptoms of childhood acute upper airway obstruction.

2. Know the differential diagnosis for childhood upper airway obstruction.

3. Know the principles of acute management of childhood upper airway obstruction.

Considerations

This child’s good health just prior to developing respiratory symptoms is a major clue to his diagnosis. Foreign body aspiration or anaphylactic responses to an allergen are the two most likely explanations for his sudden symptoms. The additional information that the child was playing alone with another child suggests a scenario whereby the older child may have “shared” a toy, a piece of candy, or another enticing object with our patient. Stridor may be easily confused for wheezing by less experienced clinicians, which might lead one to also consider lower respiratory etiologies in the differential diagnosis. Stridor, however, is characterized by its monophonic sound (ie, a single pitch) that is louder over the upper chest. In contrast, wheezing represents blockage of multiple small airways and is heard as a polyphonic sound (ie, multiple pitches), heard best with the stethoscope placed over the lung bases.

APPROACH TO:

Suspected Foreign Body Aspiration

DEFINITIONS

STRIDOR: A high-pitched, monophonic harsh sound that is usually inspiratory; it results from upper airway obstruction. The obstruction may be supraglottic (ie, above the vocal cords), glottic, and/or subglottic (ie, below the vocal cords).

TACHYPNEA: A respiratory rate that is faster than normal for the person’s age. The resting respiratory rate for an infant or young child is faster than that of an older person. The average resting respiratory rate for an infant is 30 breaths/min, whereas an 8-year-old child breathes at 20 breaths/min, and an adult breathes at a rate of approximately 16 breaths/min.

DYSPNEA:A subjective difficulty in breathing. Patients may describe it as feeling “short of breath.”

ATELECTASIS: Collapse of a portion of the lung. Atelectasis may be due to intrinsic factors, such as blockage of the airway proximal to the atelectatic tissue, or extrinsic factors, such as a pneumothorax.

CLINICAL APPROACH

Foreign body aspiration is a common cause of respiratory distress in young children and is a major cause of morbidity and mortality in this age group. Children younger than 3 years of age typically explore their environment by putting objects in their mouths. Commonly aspirated objects include nuts, popcorn, seeds, raw carrot and hot dog pieces, grapes, candies, small toys, and coins. Objects that lodge in the larynx or trachea can cause rapid asphyxia and death if not dislodged immediately. These usually present with respiratory distress, cough, and stridor; aphonia (“hoarseness”) may also be present. More commonly, objects lodge in a bronchus and present with cough, wheezing, and decreased breath sounds over the affected side. Atelectasis or pneumonia may later develop. About 20% of cases are not diagnosed until 1 month after the incident, since an aspirated foreign body in the bronchus can mimic other causes of chronic cough and wheezing. Foreign bodies in the esophagus may also induce respiratory symptoms through pressure exerted on the membranous trachea. A carefully obtained history describing the child’s state just prior to the onset of symptoms, physical examination, and a complete review of systems is key to making the correct diagnosis. Bronchoscopy should be performed if these suggest aspiration even if x-rays are normal.

The general differential diagnosis for a child with stridor, tachypnea, and chest retractions includes infectious and other noninfectious etiologies. A child with fever, hoarseness, a “barky” cough, and a recent history of rhinorrhea or congestion may have croup (laryngotracheobronchitis). A variety of viruses have been implicated, the most common being parainfluenza. X-ray of the neck may show a tapered subglottic airway (“steeple sign”). Epiglottitis(rare as a result of widespread Haemophilus influenzaeb vaccination) is identified by its characteristic clinical signs: drooling, a preference to sit in a tripod or upright position (“sniffing” position), muffled vocalizations, inspiratory stridor, and absence of cough. Identification of epiglottitis is crucial because the high risk for sudden complete airway obstruction necessitates immediate care. Bacterial tracheitis caused by Staphylococcus aureus (or less commonly Moraxella catarrhalis or nontypeable H influenzae) can occur as a sequela 5 to 7 days after viral croup. Like epiglottitis, bacterial tracheitis can cause life-threatening airway obstruction and thus may require emergent intubation or tracheostomy. Noninfectious causes mimicking foreign body aspiration include retropharyngeal abscess, angioedema, tracheomalacia, extrinsic airway compression (aortic/vascular ring, tumor), and intraluminal obstruction (papilloma, hemangioma). The term spasmodic croup is used to describe the syndrome of sudden nighttime onset of hoarseness, “barky” cough, and inspiratory stridor in a previously healthy, afebrile child. Viral infections, respiratory allergies, gastroesophageal reflux, and psychosocial factors are implicated as possible etiologies for spasmodic croup.

Some aspirated objects (eg, a metal coin) are easily visualized on radiographs, and their appearance indicates their location. Coins lodged in the trachea appear as a line on the AP radiograph because the cartilaginous rings on the anterior side of the trachea force the coin into this position. Coins in the esophagus result in dysphagia and milder respiratory symptoms; they appear as circles on AP radiograph. Objects that are small enough to pass beyond the carina most typically lodge in the right mainstem bronchus, because it is more vertical than the left bronchus. Objects made of plastic and other radiolucent materials are not visible on radiographs, although there may be other radiographic clues, such as air trapping where the obstructed lung remains inflated on a PA expiratory film and the mediastinum may be shifted toward the normal lung’s side. Rigid bronchoscopy is diagnostic and therapeutic in cases of foreign body aspiration into an airway; endoscopy can be used if the object is in the esophagus.

COMPREHENSION QUESTIONS

59.1 A 7-month-old boy with respiratory difficulty is brought to the emergency department at 3 AM. His mother reports that several family members have had “colds” over the past week. He first developed cough and coryza 3 days ago, and the cough has become “barky.” On examination, he has an axillary temperature of 100.4°F (38°C), respiratory rate 55 breaths/min, and heart rate 140 bpm (beats/min). A moderately inflamed pharynx and inspiratory stridor are noted on physical examination. Which of the following is the next step in management of this patient?

A. Reassure the child’s parents that his upper respiratory symptoms will resolve without antibiotics or other medication.

B. Obtain a chest radiograph.

C. Obtain a throat swab specimen for rapid testing for Streptococcus pyogenes.

D. Administer aerosolized racemic epinephrine and corticosteroids immediately.

E. Obtain blood, urine, and cerebrospinal cultures, and begin parenteral antibiotics.

59.2 A 14-month-old girl has a 6-hour history of fever to 102.6°F (39.2°C) and an increasingly ill appearance. She is anxious and does not want to leave her mother’s arms, but she gives only a faint cry when approached. Her respiratory rate is 70 breaths/min and her neck is hyperextended. An area of moisture is noted on the shoulder of the mother’s blouse. Which of the following is the next most appropriate step in management?

A. Perform a complete physical examination with particular emphasis on the mouth and upper airway.

B. Immediately secure the airway with an endotracheal tube in the emergency department.

C. Arrange for immediate transfer to the operating room to secure the airway through tracheal intubation or tracheostomy.

D. Administer aerosolized racemic epinephrine and nebulized steroids.

E. Obtain blood, urine, and cerebrospinal cultures, and begin parenteral antibiotics.

59.3 A 2-year-old boy is seen in your clinic after his parents report a “rough night.” Following a few days of a mild upper respiratory symptoms but no fever, last night he had an episode of stridor and increased effort of breathing. He has done this twice previously in the last 2 months and was well before each episode. In the interim period he has been normal. Today, apart from some mild rhinorrhea, his physical examination is normal. Which of the following is the most likely etiology?

A. Spasmodic croup

B. Foreign body aspiration

C. Tracheomalacia

D. Extraluminal compression of the trachea by a tumor

E.S pyogenes pharyngitis

59.4 A 2-year-old boy with a 3-day history of upper respiratory congestion and cough now has inspiratory stridor, respiratory rate of 50 breaths/min, chest retractions, and a fever of 101°F (38.3°C). The next step in the management of his condition should be which of the following therapies?

A. Pseudoephedrine and dextromethorphan

B. Albuterol and cromolyn

C. Ampicillin and gentamicin

D. Cool mist and herbs

E. Aerosolized racemic epinephrine and steroids

ANSWERS

59.1 D. This child’s history and physical examination findings are typical of croup. Croup often presents at night when symptoms typically worsen. Cool mist is often used in an attempt to relieve laryngeal spasm; the evidence supporting its effectiveness is weak except in cases of allergic (spasmodic) croup. Aerosolized epinephrine and oral or aerosolized steroids are effective in reducing airway edema and relieving croup symptoms. Potentially irritating procedures (ie, use of tongue blades or needle sticks) are avoided unless necessary; agitation and crying aggravate the respiratory symptoms. Parenteral fluids rarely may be indicated if the child is not drinking well. Oxygen saturation should be monitored closely; a low saturation in croup indicates imminent airway obstruction.

59.2 C. This child’s clinical picture is consistent with epiglottitis, a medical emergency. She is kept calm and is transported to an operating room where the airway is examined and secured by a surgeon and anesthesia team skilled in tracheal intubation and tracheostomy. Visualizing the pharynx in the emergency department may cause airway obstruction. Although rare in the United States, epiglottitis occasionally is seen in hypoimmunized children or as a result of infection with S pyogenes, S pneumoniae, or S aureus.

59.3 A. Children with spasmodic croup appear well during the daytime but develop nocturnal stridor and difficulty breathing; the cause is unknown. As this child’s symptoms resolved during the daytime and he previously has had two similar episodes, foreign body aspiration is less likely (although always considered in a toddler with respiratory distress). Infants with mild tracheomalacia have stridor only intermittently (eg, with crying), but it is first noted in early infancy. A tumor compressing the trachea usually causes persistent or progressive symptoms but less likely intermittent stridor. Streptococcal pharyngitis causes fever and throat pain but generally not significant stridor.

59.4 E. Aerosolized epinephrine and steroids are the only therapies that significantly improve symptoms of croup (in this case, likely viral). Systemic and nebulized steroids also reduce hospital admissions, length of hospital stay, and hospital readmission.


CLINICAL PEARLS

Image Foreign body aspiration should be considered in the differential diagnosis for a previously healthy young child with sudden onset of stridor and respiratory distress, as well as for a previously healthy child with chronic cough or wheezing.

Image The differential diagnosis of foreign body aspiration also includes croup, epiglottitis, bacterial tracheitis, tracheomalacia, extrinsic airway compression, and other forms of intraluminal obstruction. Epiglottitis and bacterial tracheitis require stabilization in a calm environment by an expert skilled in airway management. Asthma and other forms of chronic obstructive pulmonary disease should be considered for the child with wheezing.

Image Aspirated objects that pass beyond the carina usually lodge in the right mainstem bronchus.

Image Rigid bronchoscopy is both diagnostic and therapeutic in cases of foreign body aspiration.


REFERENCES

Adamiak T, Rudolph CD. Other esophageal disorders. In: Rudolph CD, Rudolph AM, Lister GE, First LR, Gershon AA, eds. Rudolph’s Pediatrics. 22nd ed. New York, NY: McGraw-Hill; 2011:1412.

Aujla SJ. Disorders causing airway obstruction. In: Rudolph CD, Rudolph AM, Lister GE, First LR, Gershon AA, eds. Rudolph’s Pediatrics. 22nd ed. New York, NY: McGraw-Hill; 2011:1949-1952.

Holinger LD. Foreign bodies of the airway. In: Kliegman RM, Stanton BF, St. Geme III J, Schor N, Behrman R, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: WB Saunders; 2011:1453-1454.

Kenna MA. Foreign-body aspiration. In: Rudolph CD, Rudolph AM, Lister GE, First LR, Gershon AA, eds. Rudolph’s Pediatrics. 22nd ed. New York, NY: McGraw-Hill; 2011:449-451.

Khan S, Orenstein SR. Ingestions. In: Kliegman RM, Stanton BF, St. Geme III J, Schor N, Behrman R, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: WB Saunders; 2011:1271.

Roosevelt GE. Acute inflammatory upper airway obstruction (croup, epiglottitis, laryngitis, and bacterial tracheitis). In: Kliegman RM, Stanton BF, St. Geme III J, Schor N, Behrman R, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: WB Saunders; 2011:1445-1450.